Mascots exist to help rile up a crowd, pose for pictures with little kids and, during games, lightly piss off the other team's players. Minnesota's Goldy Gopher, it seems, took that a step too far.
In the clip, Goldy is mimicking a Penn State player while holding his nose. No one really has a problem with that. Then the Penn State player takes a knee and begins a pre-game prayer. Goldy mimics him throughout the prayer and gets up to again hold his nose at the player. Not cool.
There are just some things that are off limits for mascots to poke fun at. Generally, racial stereotypes are the biggest no-no. Disability is high up there too and I think religion has to be as well.
Unfortunately, MSU is sitting in a bit of a glass house on this one as I'm sure many universities with mascots are. Back in 2003, Sparty did a "blind ref" sketch video for a mascot competition that the Council for Students with Disabilities found out about (because he happened to stumble into a CSD event at the Union while wearing a ref jersey and using a cane). Full disclosure, while at school I was a member of CSD and, while I wasn't there for this incident, fully supported their condemnation.
On balance, however, the Sparty program is one of the university's biggest successes. Multiple national championships and even a video game cover have been awarded to the most recognizable college mascot in the world. Negative incidents are, thankfully, rare.
However, when they do happen the folks in charge of the Sparty program promptly apologize and change their behavior. The folks running the Goldy Gopher program at Minnesota would be wise to do the same.
Update: The University of Minnesota has issued an apology, which is reprinted in full here.